This invention relates to printers and particularly to printers that operate at relatively high speeds in response to data signals from a data source, such as a host data processing system. More particularly, the invention relates to provision of decision-making facilities in the printer subsystem to increase printing throughput. In previous printer systems or subsystems that receive data from a host system, printing throughput has been improved by analyzing the lines of data as they are presented to the printer to determine the relative line lengths and locations with respect to one another with the objective of printing the lines in the fastest manner possible. In some cases, printer units are provided with a bidirectional printing capability which enables them to print lines either from left to right or right to left on a form or document inserted in the printer. In such a printer, the lookahead analysis of lines to be printed enables the printer to move the print head to the closest end of the next succeeding line of print thus saving time during printing operations. Most of the printer units have been based on conventional wire images. That is, considering a wire matrix type of printer, the data is presented to the printer and is actually printed on the document in a sequence of vertical columns of wire dots laid down by actuation of print wires in the printer. When nonconventional print wire images are used, the wire images in the printer unit do not conform to the conventional geometrics, and it is necessary to consider many additional factors in the lookahead analysis.